Eğirdir Lake

Eğirdir Lake is Türkiye’s second-largest sweet water lake and lies within the boundaries of Isparta province. Lake is situated in a karstic region formed primarily by karstic processes during pluvial periods. With a surface area of 479 km², it is Türkiye’s fourth-largest lake and reaches a maximum water level of 918.80 metres. Eğirdir Lake plays a vital role in meeting regional drinking water and irrigation needs. The lake consists of two distinct sections: the northern, smaller part known as Hoyran Lake, and the larger southern main body, which is called Eğirdir Lake.

Eğirdir Lake lies at an elevation of 917.7 metres above sea level, is 48 kilometres long, and ranges from 3 to 15 kilometres in width. The lake is divided into two sections by the Eğirdir Strait; this strait narrows to approximately 1.8 kilometres in a north-south orientation, creating the visual impression of two separate lake basins. The lake’s perimeter is bordered by steep cliffs, which are especially prominent in the western sections.

Hydrological Characteristics

The lake’s water sources include various streams descending from surrounding mountains and springs emerging from the lakebed. The water of Eğirdir Lake is freshwater, and its water level fluctuations have been shaped by both natural factors and human interventions. In recent years, a significant change has occurred in the lake’s recharge pattern, with water withdrawals now directed to the Karacaören I and II Dams located in the Çandır Plain. Additionally, the 22-kilometre-long Kovada Canal, which naturally connects Eğirdir Lake with Kovada Lake, is another key factor influencing the lake’s hydrological regime.

Ecosystem and Biological Diversity

Eğirdir Lake is notable for its rich biological diversity. The lake’s ecosystem hosts several fish species, including Carp, Grass Carp, Pike-perch, Roach and Silver fish of the like genus. Among non-native species, predatory fish such as Pike-perch (Stizostedion lucioperca) are also present. The lake’s biological composition has been significantly altered since fish stocking programs began in 1955. The reed beds and aquatic vegetation surrounding the lake are critical to the ecosystem and are directly linked to fluctuations in water levels. Eğirdir Lake also serves as a wintering ground for numerous waterbird species, including the Eurasian Coot, Little Grebe and Black-necked Grebe, among native and migrant species.

Conservation Status and Ecological Challenges

Eğirdir Lake was declared a natural Environment site by the Ministry of Environment and Urbanization in 1996. However, the lake’s ecosystem is under threat due to various human interventions, including agricultural irrigation, urban development and unsustainable fishing practices. Changes in water levels and declines in biological diversity are disrupting the ecological balance. Furthermore, water extraction and inadequate circulation have led to deteriorating water quality and ecological harm.